Nutritional consequences of folivory in a small-bodied lemur (Lepilemur leucopus): Effects of season and reproduction on nutrient balancing

Abstract

ObjectivesSmall-bodied folivores are rare because processing leaves often requires extensive gut adaptations and lengthy retention times for fiber fermentation. However, the <1 kg nocturnal white-footed sportive lemurs (Lepilemur leucopus) persist on a leaf-based diet. We investigated how extrinsic (i.e., seasonality in temperature and food availability) and intrinsic factors (i.e., reproductive state) influence nutrient intake and explored how nutrient and energy needs are met in this species.Materials and MethodsWe conducted full night focal follows across all seasons and analyzed nutrients in all items eaten by adults of both sexes to investigate nutrient intake and nutritional priorities in L. leucopus. We estimated digestible protein content, as this is a biologically more meaningful measure than crude protein.ResultsProtein intake was constant across seasons, while non-protein energy and dry matter intake increased from the hot wet to the cold dry season. Males and females did not differ in their nutrient or apparent energy intake irrespective of female reproductive state.DiscussionWe conclude that these animals prioritize protein over non-protein energy intake as dietary protein is in limited supply, and that thermoregulation poses higher energetic costs than reproduction in this species. While protein intake did not differ across female reproductive states, the relative protein content of the diet was highest during the lactation period, indicating that the balance of non-protein to protein intake may be more important than absolute intake. Dry matter intake was high compared to other folivorous primates, indicating that L. leucopus follows an intake rather than an efficiency strategy to meet its energy requirements.